Dynamo-electric machine



(No Model.) 2 Sheets-Sheet 1.

E. A. SPERRY. DYNAMO ELECTRIC MACHINE.

No. 469,725. Patented Mar. 1, 1892.

(No Model.) 2 Sheets-Sheet 2. E. A. SPERRY.

DYNAMO ELECTRIC MACHINE. No. 469,725.

UNITED STATES PATENT OFFICE.

ELMER A. SPERRY, OF CHICAGO, ILLINOIS.

DYNAMO-ELECTRIC MACHINE.

SPECIFICATION forming part of Letters Patent No. 469,725, dated March 1, 1892. Application filed January 10 1890. Serial No. 336,591. (No model.)

To aZZ whom it may concern:

Be it known that I, ELMER A. SPERRY, a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Dynamos, of which the following is a specification. Y

My invention relates to dynamos, and has for its object to provide a simple, cheap, and convenient dynamo.

My invention is illustrated in the accompanying drawings, wherein- Figure 1 is a side view of my device. Fig. 2 is a cross-section through a detail thereof. Fig. 3 is a perspective View of the field-magnets with the armature removed.

Like parts are indicated by the same letter in all the figures.

A is the base-plate; B B, the field-magnets supported from the yoke C and having projecting from each the arc-shaped pole-pieces D D. The shaft E passes centrally between and parallel with the field-magnets B B and through the plate 0, in which it is j ournaled. At one end it carries the driving-pulley F, and at the other end the commutator G, and it is journaled in the standard H. Rotatably secured on the standard is the brush-holder J carrying the brushes K and L, adapted to bear upon the rotating commutator.

M M are conductors; but all of the cond uctors are not shown, as to show them is not essential for the purposes of this application. The commutator is insulated from the shaft at N.

O O are arms projecting from the shaft and forming a sort of spider, and O O are similar arms forming a similar spider.

P P are the coils of the armature, arranged upon the annular body R. this body pass the supporting-rods,

suitably Through of which there may be any convenient number S. These rods are suitably shouldered at T T, their outer extremities being secured by the nuts U U on the arms of the spider. At the extremity of the rods S, where they pass through the coils P P, they are flattened, as shown in Fig. 4:, to permit of the winding of the coils without great displacement thereof. In this manner and by use of the double spiders the armature is supported very rigidly, and may be rotated in very close proximity to the polepieces D D.

In certain patterns of machines the inner spider may notbe indispensable; but it is well in designing machines of this character to adopt a general form that will be desirable for all styles and patterns of machines or for the greatest number.

The use and operation of my invention will be readily understood. The shaft being rotated in the usual manner the armature is car ried with it, rotating with the shaft about the center thereof as a center, and being securely and firmly held in position within, but very close to the inner surfaces of the arc-shaped pole-pieces D D. The current generated is distributed in the usual manner.

Having thus described my invention, what I claim, and desire to secure by Letters Patcut, is as follows:

In a dynamo, the combination of a rotating shaft with an annular armature, rods passing thro ugh the same, a supporting-spider for such rods, said rods flattened at the point or points where the armature-coils pass them, and a field-magnet.

ELMER A. SPERRY.

Witnesses:

GELEsTE. P. CHAPMAN, DAVIDA J. JOHNSON. 

